[mythtv-users] Jitter and artifacts

[Joel Anderson]

> Joel Anderson wrote:
>
> >>>I've been searching the archives for a while now and can't seem to
> >>>nail a couple of issues down. When watching live TV every once in a
> >>>while a quick jitter or wierd artifacts of a similar frame flash on
> >>>the screen. Its sparatic and sometimes doesn't happen right away or
> >>>even after a while .. nothing consistent. I read in a post on the
> >>>forums it _may_ be from having the S-Video and Comp inputs running at
> >>>the same time. I'm wondering if anyone has seen this. I would have to
> >>>redo all my channel assignments if this is the case.
> >>>
> >>>Right now I have channels over 60 (99-500) on S-Video, and channels
> >>>under (2-60) going through the tuner.
> >>>
> >>>Another thing I can't seem to get rid of no matter how much I tinker
> >>>with bitrate etc, is the jittery audio and video at the end of a
> >>>program or movie. Its like the blank frame detection goes into
> >>>overdrive when there is a lot of black on the screen even if its laced
> >>>with a bunch of text. I've enabled jitter control (which I'm not even
> >>>sure is related to this). Is this normal or is there a way to get rid
> >>>of it?
> >>>
> >>>I'm running the CVS version of everything.
> >>>
> >>>--
> >>>Lonny
> >>>
> >>>
> >>>
> >>Yes, I am seeing exactly the same thing. I have a PVR 250, a Radeon 8500
> >>in a AU13 mobo with an xp2100+. I recorded Terminator 3 the other night.
> >>The intro/credits is very dark, and the audio cut in and out during the
> >>playback but the rest of the movie was fine.  I also see sporadic
> >>artifacts during live Tv watching. I am new to Myth and still
> >>configuring stuff so had assumed it was my setup, but maybe not.
> >>
> >>Too bad some one hijacked this thread for another topic (which became a
> >>flame war) because I have no doubt nobody is still reading this
thread...
> >>
> >>Tim
> >>
> >>
> >
> >I'm still reading it.  ;)
> >
> >I see the same flickering artifact of what looks like parts of the
current
> >frame in my recorded programs.  Not sure about live tv, I don't use it
much
> >ATM.  I see this playing back in Myth and also with WMP via MythWeb on my
> >WinXP box, so It would seem to be an ivtv driver issue on the capture
end.
> >I'm using a PVR-250 on a PII-350 for my backend, running 0.15.1 on FC1
with
> >everything updated from Axel's rpms.
> >
> >Joel
> >
> >
> I am running Knoppix 3.4 5-17-english (2.4.26) on HD, with the latest
> debian (15.1) myth packages, and ivtv 0.1.9 with the cardtype patch
> (forgot to say I have the 250MCE version). What version of ivtv are you
> running?

That's a good question, 0.1.9-26 from atrpms.  Not sure if that's specific
enough for you, but that's all I can see from a quick look at what's
installed.  I just let apt-get upgrade everything as much as possible.  Yep,
lazy - I know.  ;)

> I don't think I see artifacts in recorded programs but I have only used
> it a little and the problem is intermittent so can't be sure. The eye
> tends to naturally filter that stuff out after a while. There was a
> thread somewhere that mentioned strange PVR250 artifacts at lower
> quality  settings (definition?). I have since bumped up mine from the
> defaults but have not tested it enough to comment yet.
>
> I only have composite and tuner hooked up, not s-video.
>
> Tim
>

The artifacts don't seem to appear in my 480x480 at 5000kbps recordings, at
least in the few I looked at.  I record more at 480x480 at 2200kbps to save
space, which I definitely has these artifacts.  I'll set my default profile
higher and see what happens.

Joel